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From: "tromey at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: java-prs@gcc.gnu.org
Subject: [Bug java/21855] array bounds checking elimination
Date: Tue, 10 Jan 2012 17:22:00 -0000	[thread overview]
Message-ID: <bug-21855-8172-SDJzd5WCYX@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-21855-8172@http.gcc.gnu.org/bugzilla/>

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21855

--- Comment #24 from Tom Tromey <tromey at gcc dot gnu.org> 2012-01-10 17:21:02 UTC ---
I found my code and it turns out I never finished it.
(I did write a java-specific devirtualization pass.)
Here is an introductory comment that explains my plans:

/* This pass implements a few simple gcj-specific optimizations
   related to handling of invariants.  In Java, certain fields of
   some objects are known to be invariant after the object has been
   created.  For instance, the vtable pointer of an object cannot
   change; neither can the length of an array.

   Also, this pass knows that 'new Type[n]' sets the length of an
   array to 'n'.

   Ideally GCC would recognize these cases and optimize for us.
   However, currently there is no way to express these properties to
   the optimizers.
 */


  parent reply	other threads:[~2012-01-10 17:22 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <bug-21855-8172@http.gcc.gnu.org/bugzilla/>
2012-01-10 15:43 ` [Bug tree-optimization/21855] " rguenth at gcc dot gnu.org
2012-01-10 15:53 ` aph at gcc dot gnu.org
2012-01-10 16:20 ` [Bug java/21855] " rguenth at gcc dot gnu.org
2012-01-10 16:28 ` aph at gcc dot gnu.org
2012-01-10 16:31 ` rguenth at gcc dot gnu.org
2012-01-10 16:36 ` rguenth at gcc dot gnu.org
2012-01-10 16:46 ` aph at gcc dot gnu.org
2012-01-10 16:58 ` rguenth at gcc dot gnu.org
2012-01-10 16:59 ` rguenth at gcc dot gnu.org
2012-01-10 17:08 ` aph at gcc dot gnu.org
2012-01-10 17:18 ` tromey at gcc dot gnu.org
2012-01-10 17:22 ` tromey at gcc dot gnu.org [this message]
2015-10-20 15:08 ` aph at gcc dot gnu.org

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